A wide range of agricultural implements are known and are presently in use, particularly designed for towing behind a work vehicle, such as a tractor. In one family of such implements, including tillers, planters, and so forth, a wide swath of ground can be tilled, planted, or otherwise worked in each pass of the implement in a tilled or unfilled field. Planters or air seeders, for example, often include frames supported by series of wheels and a tool bar extending transversely with respect to a line of movement of the implement across the field. Attached to the tool bar are a series of row units for dispensing seeds in parallel rows either in tilled or unfilled soil. A pair of seed tanks are typically supported on the implement support structure, such as just forward of or over the tool bar. Large amounts of seed may be poured into these tanks and, as the implement is advanced across the field, seeds are transferred from the tanks by a distribution system connected to the row units.
The seeds dispensed from the tanks pass through seed distribution systems, such as induction boxes, under the influence of gravity which moves the seeds downwardly from the tank into the distribution system. Once in the distribution system, many different motive systems are utilized, such as air flows directed into the induction box, to move the seeds through the system and into row meters that in turn deliver the seeds into furrows or trenches formed in the ground over which the planter is travelling.
As the seeds move out of the tanks and through the distribution system under the influence of gravity and the air flow entering the distribution system, bridging is the main problem that occurs with the seeds. Bridging is caused by the seeds flowing through the same path in the system at the same time where they contact one another to form a bridge across the system. Further, the weight of the seeds packing tightly enough against one another in the box that the seeds become engaged with one another as a solid mass, such that the seeds no longer flow in a fluid manner through the induction box. In addition, sticky seed treatments that are often applied to the seeds increase the adherence of the seeds to one another, consequently increasing both the occurrences of bridging and the strength of the adherence of the seeds to one another when bridging does occur.
To assist in maintain the separation of the seeds in the distribution system and/or to break up bridging between the seeds when it occurs, distribution systems often employ vibration devices. These devices are most often secured to a housing for the distribution system, such as the induction box, and allows the seeds to fluidize as they flow through the inductor box. The vibrations provided to the box by the vibration device helps to prevent bridging and slugging during system operation, and maintains the air/seed mix ratio in a steady state. Many different types of vibrators or vibration devices are currently in use on existing distribution system including hydraulic, pneumatic, and electric devices,
While these vibration devices are effective in reducing the occurrences of bridging of the seeds in the distribution systems, these devices have the drawbacks of requiring a separate operating structure from the distribution system, especially in the case of mechanical and hydraulic devices, or requiring a complex and expensive construction to effect the vibration of the seeds as required. or both.
As a result it is desirable develop a vibration device for a seed distribution system that can effectively supply vibrations to the distribution system to minimize bridging of the seeds in the distribution system without requiring a separate operating system or a complex structural addition to the distribution system.